The invention generally relates to peening hammers and more particularly to a portable peening hammer having an improved peening head through the use of which is achieved effects similar to the effects achieved when employing shot-peening systems.
As is well understood by those familiar with metal working arts, peening is a process through which residual compressive stresses are imparted to the surface of ductile materials by striking the surface with an object having a hemispherical configuration. For example, the process often is performed simply by striking the surface of a selected ductile metal with a hemispherical head of a ball peen hammer.
Of course, other techniques are employed where so desired. Such techniques include the use of systems wherein steel shot is propelled at a high velocity against the surface of the metal being peened. In practice, the velocity is imparted to the shot through the use of streams of pressurized air, centrifugal force, streams of water at high pressures, and, of course, the forces of gravity.
Unfortunately, the equipment and tooling required in order to utilize pneumatic, centrifugal, hydraulic and gravity-propelled shot is dangerous, bulky, expensive, and frequently too difficult to control, particularly when peening small surface areas such as those found on thin forging pads provided for space vehicles. For example, shot peening processes often require the use of stationary systems located in workshops and the like. Hence components to be peened must be transported from a given location to a shop, often remotely located. Moreover, as can readily be appreciated, the high velocity of the shot and the high pressures of the streams of air and water employed in propelling the shot creates a safety hazard, and, of course, the spent shot tends to contaminate the immediate vicinity. Another disadvantage encountered when employing shot-peening systems is attributable to the fact that spent shot tends to establish a protective shield for a surface being peened so that a loss of energy and change of direction is experienced by live shot striking spent shot. Thus the effectiveness of such systems is substantially reduced.
As should, therefore, readily be apparent, there currently exists a need for an improved portable peening gun which can be transported and readily employed in manually performing peening operations for thereby avoiding the difficulties heretofore encountered in employing shot-peening equipment.
It is, therefore, the general purpose of the instant invention to provide an improved portable peening gun capable of being employed for effectively and rigidly peening the surface areas of components mounted in fixed relation with supporting structure, for example, thin forgings mounted on Saturn S-1B vehicles.